Study of the process ${e}^{+}{e}^{-}\to p\overline{p}$ via initial state radiation at BESIII

The Born cross section for the process ${e}^{+}{e}^{-}\to p\overline{p}$ is measured using the initial state radiation technique with an undetected photon. This analysis is based on datasets corresponding to an integrated luminosity of $7.5\text{}\text{}{\mathrm{fb}}^{-1}$, collected with the BESIII detector at the BEPCII collider at center of mass energies between 3.773 and 4.600 GeV. The Born cross section for the process ${e}^{+}{e}^{-}\to p\overline{p}$ and the proton effective form factor are determined in the $p\overline{p}$ invariant mass range between 2.0 and $3.8\text{}\text{}\mathrm{GeV}/{c}^{2}$ divided into 30 intervals. The proton form factor ratio ($|{G}_{E}|/|{G}_{M}|$) is measured in 3 intervals of the $p\overline{p}$ invariant mass between 2.0 and $3.0\text{}\text{}\mathrm{GeV}/{c}^{2}$.